{
\def\sym#1{\ifmmode^{#1}\else\(^{#1}\)\fi}
\begin{tabular}{l*{4}{c}}
\toprule
                &\multicolumn{1}{c}{(1)}&\multicolumn{1}{c}{(2)}&\multicolumn{1}{c}{(3)}&\multicolumn{1}{c}{(4)}\\
                &\multicolumn{1}{c}{Any comment}&\multicolumn{1}{c}{Nonsense comment}&\multicolumn{1}{c}{Constructive comment}&\multicolumn{1}{c}{Length (characters)}\\
\midrule
\textbf{Panel A: Type of voice} &         &         &         &         \\
                &         &         &         &         \\
Instrumental    &    0.005&-0.020\sym{**}&    0.031&    7.156\\
                &  (0.037)&  (0.010)&  (0.037)& (14.183)\\
                &         &         &         &         \\
 \hline Intrinsic group  mean&     0.50&     0.03&     0.36&    98.16\\
 \hline         &         &         &         &         \\
\textbf{Panel B: Feedback announcement} &         &         &         &         \\
                &         &         &         &         \\
Feedback announcement&    0.025&   -0.005&    0.004&34.326\sym{**}\\
                &  (0.036)&  (0.009)&  (0.036)& (13.680)\\
                &         &         &         &         \\
 \hline No feedback group mean&     0.50&     0.02&     0.38&    85.19\\
Number of Observations&      672&      672&      672&      672\\
\bottomrule
\end{tabular}
}
